Automatic Traffic Sign Detection

This work use basic image processing technique to automatically recognize two different traffic signs (stop sign and yield sign) in an image. The image is first thresholded on RBG domain to separate out the regions with red color, which is those traffic signs usually have, then region mapping is done on the remaining regions, the regions that are either too small and too large are removed since they are unlikely to be a traffic sign. Since these two traffic sign is either triangle or octagon in shape, both have the major axis to minor axis ratio close to one, those regions whose ratio is too large is also removed. Finally, the filling ratio of a region is used to separate stop sign from yield sign. This scheme are tested on an total of 65 images with 52 images have stop signs and 13 have yield sign, the overall correct recognition rate is 83%.